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1.
Ann Surg Oncol ; 30(6): 3197-3205, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36973564

RESUMEN

Worldwide, the capacity of healthcare systems and physician workforce is woefully inadequate for the surgical treatment of cancer. With major projected increases in the global burden of neoplastic disease, this inadequacy is expected to worsen, and interventions to increase the workforce of surgeons who treat cancer and strengthen the necessary supporting infrastructure, equipment, staffing, financial and information systems are urgently called for to prevent this inadequacy from deepening. These efforts must also occur in the context of broader healthcare systems strengthening and cancer control plans, including prevention, screening, early detection, safe and effective treatment, surveillance, and palliation. The cost of these interventions should be considered a critical investment in healthcare systems strengthening that will contribute to improvement in the public and economic health of nations. Failure to act should be seen as a missed opportunity, at the cost of lives and delayed economic growth and development. Surgeons who treat cancer must engage with a diverse array of stakeholders in efforts to address this critical need and are indispensably positioned to participate in collaborative approaches to influence these efforts through research, advocacy, training, and initiatives for sustainable development and overall systems strengthening.


Asunto(s)
Neoplasias , Cirujanos , Oncología Quirúrgica , Humanos , Atención a la Salud , Neoplasias/cirugía
3.
J Surg Res ; 235: 167-170, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30691791

RESUMEN

BACKGROUND: Cancer registration provides data that can be utilized to study the etiology, diagnosis, prevention, and treatment of cancer. Despite the efforts of the World Health Organization (WHO), cancer registration is still underdeveloped in low- and middle-income countries (LMICs). This is the case in Lagos, Nigeria. Lakeshore Cancer Center (LCC) sought to retrospectively collect and describe the characteristics of the patients seen in its first 2 y of existence. METHODS: A retrospective review of patient records presenting at LCC was performed. Various parameters were collected such as demographics and diagnoses. These data were used to perform a simple descriptive analysis. A series of consultations determined what parameters to include in the registry. CanReg, a cancer registration application, was customized to include these parameters. RESULTS: Between July 2014 and June 2016, a total of 226 cancer incidence cases were presented at LCC. There was an increasing number of new cancer cases when evaluated at 6-mo intervals. The most common cancers presented were breast (38%), prostate (12%), and colorectal (8%) cancers. The majority of patients (85%) were presented at later cancer stages. CONCLUSIONS: Breast, prostate, and colorectal cancers were the three most common cancer cases seen at LCC. Late-stage presentation remains a challenge. These results reveal the need for early detection and screening methods to help change the stage distribution. The cancer registry will be utilized to collect cancer data and to allow for analysis and better treatment/prevention protocols. Collaboration with other academic centers in the region will facilitate the establishment of a population-based registry.


Asunto(s)
Neoplasias/epidemiología , Sistema de Registros , Países en Desarrollo , Humanos , Nigeria/epidemiología , Estudios Retrospectivos
4.
Water Sci Technol ; 78(12): 2449-2458, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30767910

RESUMEN

A comprehensive assessment of full-scale enhanced biological phosphorus removal (EBPR) plants (five plants, 19 independent tests) was undertaken to determine their effectiveness in terms of aerobic and anoxic P removal. By comparing parallel P uptake tests under only aerobic or under anoxic-aerobic conditions, results revealed that introducing an anoxic stage led to an overall P removal of on average 90% of the P removed under only aerobic conditions. This was achieved with negligible higher PHA and glycogen requirements, 30% lower overall oxygen consumption and with the simultaneous removal of nitrate, reducing up to an estimate of 70% of carbon requirements for simultaneous N and P removal. Varying fractions of denitrifying polyphosphate accumulating organisms (DPAOs), from an average of 25% to 84%, were found in different plants. No correlation was found between the DPAO fractions and EBPR configuration, season, or the concentration of any of the microbial groups measured via quantitative fluorescence in situ hybridisation. These included Type I and Type II Ca. Accumulibacter and glycogen accumulating organisms, suggesting that chemical batch tests are the best methodology for quantifying the potential of anoxic P removal in full-scale wastewater treatment plants.


Asunto(s)
Desnitrificación , Fósforo , Polifosfatos/metabolismo , Eliminación de Residuos Líquidos/métodos , Microbiología del Agua , Reactores Biológicos , Aguas Residuales
5.
Environ Microbiol ; 18(1): 50-64, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25181571

RESUMEN

Denitrification is essential to the removal of nitrogen from wastewater during treatment, yet an understanding of the diversity of the active denitrifying bacteria responsible in full-scale wastewater treatment plants (WWTPs) is lacking. In this study, stable-isotope probing (SIP) was applied in combination with microautoradiography (MAR)-fluorescence in situ hybridization (FISH) to identify previously unrecognized active denitrifying phylotypes in a full-scale WWTP with biological N and P removal. Acknowledging that different denitrifiers will have specific carbon source preferences, a fully (13)C-labelled complex substrate was used for SIP incubations, under nitrite-reducing conditions, in order to maximize the capture of the potentially metabolically diverse denitrifiers likely present. Members of the Rhodoferax, Dechloromonas, Sulfuritalea, Haliangium and Thermomonas were represented in the 16S rRNA gene clone libraries from DNA enriched in (13)C, with FISH probes optimized here for their in situ characterization. FISH and MAR confirmed that they were all active denitrifiers in the community. The combined approach of SIP and MAR-FISH represents an excellent approach for identifying and characterizing an un-described diversity of active denitrifiers in full-scale systems.


Asunto(s)
Reactores Biológicos/microbiología , Comamonadaceae/genética , Desnitrificación/genética , Aguas del Alcantarillado/microbiología , Purificación del Agua/métodos , Autorradiografía , Carbono/química , Isótopos de Carbono/química , Comamonadaceae/metabolismo , Biblioteca de Genes , Hibridación Fluorescente in Situ , Nitritos/metabolismo , Nitrógeno/metabolismo , ARN Ribosómico 16S/genética
6.
Appl Microbiol Biotechnol ; 100(19): 8507-21, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27270599

RESUMEN

Membrane bioreactors (MBRs) are an advanced technology for wastewater treatment whose wide application has been hindered by rapid fouling of the membranes. MBRs can be operated with long sludge retention time (SRT), a crucial parameter impacting microbial selection in the reactor. This also affects filtration performance, since a major fouling agent are the extracellular polymeric substances (EPS). In this study, the impact of the SRT on the ecophysiology of the MBRs and, consequently, on membrane fouling was evaluated. A MBR was operated under a SRT of 60 days followed by a SRT of 20 days. A comprehensive analysis of the microbial community structure and EPS proteins and polysaccharide profiles of the mixed liquor and cake layer was carried out throughout both operation periods. The results of this study showed that the imposition of a shorter SRT led to a shift in the dominant bacterial populations. The mixed liquor and cake layer communities were very different, with Actinomycetales order standing out in the cake layer at SRT of 20 days. Overall, higher EPS concentrations (particularly proteins) were found at this SRT. Furthermore, EPS profiles were clearly affected by the SRT: it was possible to correlate a group of soluble EPS proteins with the SRT of 60 days, and a lower sludge age led to a lower diversity of polysaccharide sugar monomers, with an increase of glucose and galactose in the cake layer. This study improves our knowledge regarding the molecular reasons for fouling, which may contribute to improve MBR design and operation.


Asunto(s)
Proteínas Bacterianas/análisis , Reactores Biológicos/microbiología , Biota , Membranas/microbiología , Polisacáridos Bacterianos/análisis , Factores de Tiempo , Aguas Residuales , Purificación del Agua/métodos
7.
J Am Chem Soc ; 135(17): 6669-76, 2013 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-23544768

RESUMEN

Prior investigations into the synthesis of colloidal CdSe nanocrystals with a wurtzite crystal structure (wz-CdSe) have given rise to well-developed methods for producing particles with anisotropic shapes such as rods, tetrapods, and wires; however, the synthesis of other shapes has proved challenging. Here we present a seed-mediated approach for the growth of colloidal, shape-controlled wz-CdSe nanoparticles with previously unobserved morphologies. The synthesis, which makes use of small (2-3 nm) wz-CdSe nanocrystals as nucleation sites for subsequent growth, can be tuned to selectively yield colloidal wz-CdSe nanocubes and hexagonal nanoplatelets in addition to nanorod and bullet-shaped particles. We thoroughly characterize the morphology and crystal structures of these new shapes, as well as discuss possible growth mechanisms in the context of control over surface chemistry and the nucleation stage.

8.
Water Sci Technol ; 68(9): 1959-68, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24225095

RESUMEN

Metagenomics enables studies of the genomic potential of complex microbial communities by sequencing bulk genomic DNA directly from the environment. Knowledge of the genetic potential of a community can be used to formulate and test ecological hypotheses about stability and performance. In this study deep metagenomics and fluorescence in situ hybridization (FISH) were used to study a full-scale wastewater treatment plant with enhanced biological phosphorus removal (EBPR), and the results were compared to an existing EBPR metagenome. EBPR is a widely used process that relies on a complex community of microorganisms to function properly. Insight into community and species level stability and dynamics is valuable for knowledge-driven optimization of the EBPR process. The metagenomes of the EBPR communities were distinct compared to metagenomes of communities from a wide range of other environments, which could be attributed to selection pressures of the EBPR process. The metabolic potential of one of the key microorganisms in the EPBR process, Accumulibacter, was investigated in more detail in the two plants, revealing a potential importance of phage predation on the dynamics of Accumulibacter populations. The results demonstrate that metagenomics can be used as a powerful tool for system wide characterization of the EBPR community as well as for a deeper understanding of the function of specific community members. Furthermore, we discuss and illustrate some of the general pitfalls in metagenomics and stress the need of additional DNA extraction independent information in metagenome studies.


Asunto(s)
Bacterias/metabolismo , Metagenoma , Fósforo/metabolismo , Eliminación de Residuos Líquidos , Aguas Residuales/microbiología , Contaminantes Químicos del Agua/metabolismo , Bacterias/genética , Betaproteobacteria/clasificación , Betaproteobacteria/genética , Betaproteobacteria/metabolismo , Biota , ADN Bacteriano/análisis , Dinamarca , Secuenciación de Nucleótidos de Alto Rendimiento , Hibridación Fluorescente in Situ , Filogenia , Análisis de Secuencia de ADN , Aguas Residuales/análisis
9.
Nanomaterials (Basel) ; 13(22)2023 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-37999283

RESUMEN

In the rapidly emerging field of biomedical applications, multifunctional nanoparticles, especially those containing magnetic and plasmonic components, have gained significant attention due to their combined properties. These hybrid systems, often composed of iron oxide and gold, provide both magnetic and optical functionalities and offer promising avenues for applications in multimodal bioimaging, hyperthermal therapies, and magnetically driven selective delivery. This paper focuses on the implementation of advanced characterization methods, comparing statistical analyses of individual multifunctional particle properties with macroscopic properties as a way of fine-tuning synthetic methodologies for their fabrication methods. Special emphasis is placed on the size-dependent properties, biocompatibility, and challenges that can arise from this versatile nanometric system. In order to ensure the quality and applicability of these particles, various novel methods for characterizing the magnetic gold particles, including the analysis of their morphology, optical response, and magnetic response, are also discussed, with the overall goal of optimizing the fabrication of this complex system and thus enhancing its potential as a preferred diagnostic agent.

10.
Wound Repair Regen ; 18(1): 38-49, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20082680

RESUMEN

The bacterial microbiota plays an important role in the prolonged healing of chronic venous leg ulcers. The present study compared the bacterial diversity within ulcer material from 14 skin graft operations of chronic venous leg ulcers using culture-based methods and molecular biological methods, such as 16S rRNA gene sequencing, fingerprinting, quantitative polymerase chain reaction, and fluorescence in situ hybridization. Each wound contained an average of 5.4 species but the actual species varied between wounds. The diversity determined by culture-based methods and the molecular biological methods was different. All the wounds contained Staphylococcus aureus, whereas Pseudomonas aeruginosa was in six out of 14 wounds. Molecular methods detected anaerobic pathogens in four ulcers that were not detected with anaerobic culture methods. Quantitative polymerase chain reaction was used to compare the abundance of S. aureus and P. aeruginosa at different locations in the ulcers and their numbers varied greatly between samples taken at different locations in the same ulcer. This should be considered when ulcers are investigated in routine clinical care. The differences between the results obtained with culture-based and molecular-based approaches demonstrate that the use of one approach alone is not able to identify all of the bacteria present in the wounds.


Asunto(s)
Bacterias/aislamiento & purificación , Úlcera Varicosa/microbiología , Anciano , Anciano de 80 o más Años , Bacterias/genética , Enfermedad Crónica , Dermatoglifia del ADN , Femenino , Amplificación de Genes , Humanos , Hibridación Fluorescente in Situ , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa
11.
Hawaii Med J ; 69(6 Suppl 3): 4-6, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20539993

RESUMEN

In Hawaii, health care is a commodity, not a human right: those who can afford it receive care, those who cannot often don't. As health workers and health professional students, we witness the consequences that public policies and budget considerations have on people, on patients, on the health of those that we are dedicated to assisting. Beginning with a case study, we examine the historical antecedents leading to the increasing migration of Micronesians to Hawaii, examine the special relation that (Compact of Free Association) citizens have with the United States, and seek to reframe the political discussion regarding their health care status in this state as a debate in which medical considerations, not political or economic ones, should be the primary voice.


Asunto(s)
Política de Salud , Accesibilidad a los Servicios de Salud , Disparidades en Atención de Salud , Derechos Humanos , Seguro de Salud , Emigración e Inmigración/historia , Hawaii , Política de Salud/historia , Accesibilidad a los Servicios de Salud/economía , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Micronesia/etnología , Política
12.
Angew Chem Int Ed Engl ; 49(29): 4878-97, 2010 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-20544758

RESUMEN

One key goal of nanocrystal research is the development of experimental methods to selectively control the composition and shape of nanocrystals over a wide range of material combinations. The ability to selectively arrange nanosized domains of metallic, semiconducting, and magnetic materials into a single hybrid nanoparticle offers an intriguing route to engineer nanomaterials with multiple functionalities or the enhanced properties of one domain. In this Review, we focus on recent strategies used to create semiconductor-metal hybrid nanoparticles, present the emergent properties of these multicomponent materials, and discuss their potential applicability in different technologies.

13.
Cureus ; 12(6): e8554, 2020 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-32670691

RESUMEN

Septic cavernous sinus thrombosis (CST) is an extremely rare diagnosis that is characterized by nonspecific signs and symptoms. It is often precipitated by a recent facial or sinus infection, as the venous supply from these areas drains into the cavernous sinus. This case highlights significant morbidity and mortality in septic CST where all aggressive treatments did not lead to clinical improvement, and the precipitating cause of the thrombosis was never found. The patient reported herein decompensated despite several investigations and treatment measures due to the lack of proper evidence-based approach.

14.
Nanoscale ; 12(39): 20543, 2020 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-33020789

RESUMEN

Correction for 'Photothermal conversion of gold nanoparticles for uniform pulsed laser warming of vitrified biomaterials' by Yilin Liu et al., Nanoscale, 2020, 12, 12346-12356, DOI: 10.1039/D0NR01614D.

15.
Nanoscale ; 12(23): 12346-12356, 2020 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-32490463

RESUMEN

Pulsed laser (ms, 1064 nm) gold nanoparticle (GNP) heating has been used recently to achieve fast (>10 000 000 °C min-1) warming of vitrified droplets using gold nanorods (GNRs) as photon-absorbers. To maximize the viability of biomaterials in vitrified droplets, the droplets must be warmed as uniformly as possible. A potential approach to such warming is to use an appropriate combination of photon-absorption and -scattering to distribute heat more uniformly throughout a droplet. To investigate this, 2 plasmonic gold nanorods (GNRs), 1 hollow gold nanoshell, and 2 silica-core gold nanoshells (GNSs) were synthesized and characterized under 1064 nm laser irradiation in water, propylene glycol, and protein-rich (egg white) solutions. Using a modified cuvette laser calorimetry experiment with complementary Monte Carlo modeling, the GNSs were found to have higher per-particle absorption and scattering cross sections, while the GNRs had higher photothermal conversion efficiency, absorption efficiency, and Au mass normalized absorption cross sections. In the characterization, the GNSs with larger scattering-to-absorption ratios could have ∼30% over-estimation of photothermal conversion efficiency if scattering and reabsorption inside the solution were not considered, while GNRs with lower ratios were less impacted. Combined Monte Carlo and COMSOL simulations were used to predict the specific absorption rate (W m-3) and heating behavior of GNP-loaded hemispherical droplets, thereby demonstrating that the GNS case with higher scattering-to-absorption ratio achieved more uniform heating than the GNR case. Interestingly, further tuning of the scattering and absorption coefficients of the hemispherical GNP-loaded droplet within the model suggests the ability to obtain an optimal scattering-to-absorption ratio for uniform heating. These results show the importance of considering the reabsorption of scattered light to accurately characterize the photothermal conversion efficiency of GNP solutions during laser irradiation. We also show that the relative scattering and absorption properties of the nanoparticles can be designed to promote both rapid and uniform laser rewarming of vitrified droplets for application in cryopreservation.


Asunto(s)
Nanopartículas del Metal , Nanotubos , Materiales Biocompatibles , Oro , Rayos Láser
16.
APMIS ; 128(3): 220-231, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31709616

RESUMEN

Pseudomonas aeruginosa is generally described as ubiquitous in natural settings, such as soil and water. However, because anecdotal observations and published reports have questioned whether or not this description is true, we undertook a rigorous study using three methods to investigate the occurrence of P. aeruginosa: We investigated environmental samples, analyzed 16S rRNA data, and undertook a systematic review and meta-analysis of published data. The environmental sample screening identified P. aeruginosa as significantly associated with hydrocarbon and pesticide-contaminated environments and feces, as compared to uncontaminated environments in which its prevalence was relatively low. The 16S rRNA data analysis showed that P. aeruginosa sequences were present in all habitats but were most abundant in samples from human and animals. Similarly, the meta-analysis revealed that samples obtained from environments with intense human contact had a higher prevalence of P. aeruginosa compared to those with less human contact. Thus, we found a clear tendency of P. aeruginosa to be present in places closely linked with human activity. Although P. aeruginosa may be ubiquitous in nature, it is usually scarce in pristine environments. Thus, we suggest that P. aeruginosa should be described as a bacterium largely found in locations associated with human activity.


Asunto(s)
Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/aislamiento & purificación , Animales , Ambiente , Microbiología Ambiental , Humanos , Infecciones por Pseudomonas/microbiología , ARN Ribosómico 16S/genética
17.
Appl Environ Microbiol ; 75(10): 3127-36, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19304820

RESUMEN

Communities of ammonia-oxidizing archaea (AOA) and bacteria (AOB) in freshwater sediments and those in association with the root system of the macrophyte species Littorella uniflora, Juncus bulbosus, and Myriophyllum alterniflorum were compared for seven oligotrophic to mesotrophic softwater lakes and acidic heathland pools. Archaeal and bacterial ammonia monooxygenase alpha-subunit (amoA) gene diversity increased from oligotrophic to mesotrophic sites; the number of detected operational taxonomic units was positively correlated to ammonia availability and pH and negatively correlated to sediment C/N ratios. AOA communities could be grouped according to lake trophic status and pH; plant species-specific communities were not detected, and no grouping was apparent for AOB communities. Relative abundance, determined by quantitative PCR targeting amoA, was always low for AOB (<0.05% of all prokaryotes) and slightly higher for AOA in unvegetated sediment and AOA in association with M. alterniflorum (0.01 to 2%), while AOA accounted for up to 5% in the rhizospheres of L. uniflora and J. bulbosus. These results indicate that (i) AOA are at least as numerous as AOB in freshwater sediments, (ii) aquatic macrophytes with substantial release of oxygen and organic carbon into their rhizospheres, like L. uniflora and J. bulbosus, increase AOA abundance; and (iii) AOA community composition is generally determined by lake trophy, not by plant species-specific interactions.


Asunto(s)
Archaea/clasificación , Archaea/aislamiento & purificación , Bacterias/clasificación , Bacterias/aislamiento & purificación , Biodiversidad , Agua Dulce/microbiología , Sedimentos Geológicos/microbiología , Raíces de Plantas/microbiología , Amoníaco/metabolismo , Archaea/genética , Proteínas Arqueales/genética , Bacterias/genética , Proteínas Bacterianas/genética , ADN de Archaea/química , ADN de Archaea/genética , ADN Bacteriano/química , ADN Bacteriano/genética , Concentración de Iones de Hidrógeno , Datos de Secuencia Molecular , Oxidorreductasas/genética , Filogenia , Análisis de Secuencia de ADN , Homología de Secuencia
19.
Appl Environ Microbiol ; 74(10): 3279-83, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18344332
20.
Chemphyschem ; 9(8): 1158-63, 2008 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-18442148

RESUMEN

Linear CdTe|CdSe|CdTe heterostructure nanorods are synthesized by using a colloidal sequential reactant injection technique [Shieh et al., J. Phys. Chem. B 2005, 109, 8538-8542]. The composition profiles of the individual nanorods are verified by using nanobeam elemental mapping by energy dispersive X-ray spectroscopy (EDS) and the photoluminescence emission spectra of the linear CdTe|CdSe|CdTe heterostructure nanorods are measured as a function of the temperature (down to 5 K). Photoluminescence is observed to occur from electron-hole recombination in both the CdSe core and across the heterojunction. Thermally activated trapping is found to influence both luminescence processes, thereby being more significant for the type II recombination across the CdSe|CdTe interface.

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